Methods and multi-tube CT systems are generally known. For example, reference is made to the patent application, not previously published, having the official file reference DE 10 2005 018 066.3. Such methods and CT systems can be used, for example, for measuring the blood flow through the cardiac wall by determining the wall perfusion after an application of contrast medium. In this process, a relatively limited area of the heart is continuously scanned due to the small extent in the direction of the system axis of the detectors currently available and the accumulated concentration in the cardiac wall tissue is observed. A problem here is the relatively high dose rate applied to the patient due to the prolonged scan. This strain could be reduced. In addition, it would also be desirable if it were possible to enlarge the cardiac region observed.
Reference is also made to patent application 10 2004 004 295 A1, which discloses a method for generating CT representations with the aid of a two-tube CT system with application of a contrast medium, wherein, during the CT scan, the two X-ray tubes arranged with offset angles generate two X-ray spectra with different spectral distribution and a subtraction image is generated from the CT images reconstructed separately for each X-ray spectrum.